feat: version diffs work now

tests/renderer/components/GitDiffView.test.tsx

@@ -1,6 +1,6 @@
 import React from 'react';
 import { describe, it, expect, beforeEach, vi } from 'vitest';
-import { render, screen } from '@testing-library/react';
+import { render, screen, fireEvent } from '@testing-library/react';
 import { GitDiffView } from '../../../src/renderer/components/GitDiffView/GitDiffView';
 import { useAppStore } from '../../../src/renderer/store';
 
@@ -58,6 +58,23 @@ describe('GitDiffView', () => {
           original: '# old line',
           modified: '# new line',
         }),
+        getCommitDiffContent: vi.fn().mockResolvedValue({
+          commitHash: 'abc123def456',
+          original: '--- posts/first.md\nold',
+          modified: '--- posts/first.md\nnew',
+          files: [
+            {
+              filePath: 'posts/first.md',
+              original: 'old',
+              modified: 'new',
+            },
+            {
+              filePath: 'src/main.ts',
+              original: 'const oldValue = 1;',
+              modified: 'const newValue = 2;',
+            },
+          ],
+        }),
       },
       app: {
         ...(window as any).electronAPI?.app,
@@ -79,4 +96,33 @@ describe('GitDiffView', () => {
     expect(screen.getByText('keepOriginal:true')).toBeInTheDocument();
     expect(screen.getByText('keepModified:true')).toBeInTheDocument();
   });
+
+  it('loads commit diff content when a commit tab identifier is used', async () => {
+    render(<GitDiffView filePath="commit:abc123def456" />);
+
+    const diffEditor = await screen.findByTestId('monaco-diff-editor');
+    expect(diffEditor).toBeInTheDocument();
+    expect(await screen.findByRole('combobox', { name: /changed files/i })).toBeInTheDocument();
+    expect(screen.getByRole('button', { name: /previous file/i })).toBeDisabled();
+    expect(screen.getByRole('button', { name: /next file/i })).toBeEnabled();
+    expect((window as any).electronAPI.git.getCommitDiffContent).toHaveBeenCalledWith('/repo/path', 'abc123def456');
+    expect(diffEditor).toHaveTextContent(/original:\s*old/);
+    expect(diffEditor).toHaveTextContent(/modified:\s*new/);
+    expect(screen.getByText('language:markdown')).toBeInTheDocument();
+
+    fireEvent.click(screen.getByRole('button', { name: /next file/i }));
+
+    expect(diffEditor).toHaveTextContent(/original:\s*const oldValue = 1;/);
+    expect(diffEditor).toHaveTextContent(/modified:\s*const newValue = 2;/);
+    expect(screen.getByText('language:typescript')).toBeInTheDocument();
+    expect(screen.getByRole('button', { name: /previous file/i })).toBeEnabled();
+    expect(screen.getByRole('button', { name: /next file/i })).toBeDisabled();
+
+    fireEvent.click(screen.getByRole('button', { name: /previous file/i }));
+
+    expect(diffEditor).toHaveTextContent(/original:\s*old/);
+    expect(diffEditor).toHaveTextContent(/modified:\s*new/);
+    expect(screen.getByRole('button', { name: /previous file/i })).toBeDisabled();
+    expect(screen.getByRole('button', { name: /next file/i })).toBeEnabled();
+  });
 });

tests/renderer/components/GitSidebar.test.tsx

@@ -35,6 +35,7 @@ describe('GitSidebar', () => {
         getStatus: vi.fn().mockResolvedValue({ files: [], counts: { untracked: 0, modified: 0, deleted: 0, renamed: 0, staged: 0, total: 0 } }),
         getDiff: vi.fn().mockResolvedValue({ filePath: 'posts/a.md', patch: 'diff --git a/posts/a.md b/posts/a.md' }),
         getDiffContent: vi.fn().mockResolvedValue({ filePath: 'posts/a.md', original: '', modified: '' }),
+        getCommitDiffContent: vi.fn().mockResolvedValue({ commitHash: 'abc123', original: '', modified: '' }),
         getHistory: vi.fn().mockResolvedValue([]),
         fetch: vi.fn().mockResolvedValue({ success: true }),
         pull: vi.fn().mockResolvedValue({ success: true }),
@@ -171,6 +172,72 @@ describe('GitSidebar', () => {
     expect(getStore().tabs[0]).toMatchObject({ type: 'git-diff', id: 'git-diff:posts/first.md', isTransient: false });
   });
 
+  it('single click on a commit opens a transient git-diff commit tab', async () => {
+    (window as any).electronAPI.git.getRepoState = vi.fn().mockResolvedValue({
+      isRepo: true,
+      rootPath: '/repo/path',
+      currentBranch: 'main',
+      hasRemote: true,
+    });
+    (window as any).electronAPI.git.getHistory = vi.fn().mockResolvedValue([
+      {
+        hash: 'abc123def456',
+        shortHash: 'abc123d',
+        date: '2026-02-16T10:00:00.000Z',
+        subject: 'feat: add sidebar history click',
+        author: 'Dev One',
+      },
+    ]);
+
+    render(<GitSidebar />);
+
+    const commitItem = await screen.findByRole('button', { name: /feat: add sidebar history click/i });
+
+    await act(async () => {
+      fireEvent.click(commitItem);
+    });
+
+    expect(getStore().tabs).toHaveLength(1);
+    expect(getStore().tabs[0]).toMatchObject({
+      type: 'git-diff',
+      id: 'git-diff:commit:abc123def456',
+      isTransient: true,
+    });
+  });
+
+  it('double click on a commit opens a persistent git-diff commit tab', async () => {
+    (window as any).electronAPI.git.getRepoState = vi.fn().mockResolvedValue({
+      isRepo: true,
+      rootPath: '/repo/path',
+      currentBranch: 'main',
+      hasRemote: true,
+    });
+    (window as any).electronAPI.git.getHistory = vi.fn().mockResolvedValue([
+      {
+        hash: 'abc123def456',
+        shortHash: 'abc123d',
+        date: '2026-02-16T10:00:00.000Z',
+        subject: 'feat: add sidebar history click',
+        author: 'Dev One',
+      },
+    ]);
+
+    render(<GitSidebar />);
+
+    const commitItem = await screen.findByRole('button', { name: /feat: add sidebar history click/i });
+
+    await act(async () => {
+      fireEvent.doubleClick(commitItem);
+    });
+
+    expect(getStore().tabs).toHaveLength(1);
+    expect(getStore().tabs[0]).toMatchObject({
+      type: 'git-diff',
+      id: 'git-diff:commit:abc123def456',
+      isTransient: false,
+    });
+  });
+
   it('initializes repository and refreshes repo state after clicking Initialize Git', async () => {
     const getRepoStateMock = vi
       .fn()

tests/renderer/components/TabBar.test.tsx

@@ -0,0 +1,81 @@
+import React from 'react';
+import { describe, it, expect, beforeEach, vi } from 'vitest';
+import { render, screen } from '@testing-library/react';
+import { TabBar } from '../../../src/renderer/components/TabBar/TabBar';
+import { useAppStore } from '../../../src/renderer/store';
+
+describe('TabBar', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+
+    (window as any).addEventListener = vi.fn();
+    (window as any).removeEventListener = vi.fn();
+
+    if (!(globalThis as any).ResizeObserver) {
+      (globalThis as any).ResizeObserver = class {
+        observe() {}
+        disconnect() {}
+      };
+    }
+
+    useAppStore.setState({
+      activeProject: {
+        id: 'project-1',
+        name: 'Test Project',
+        slug: 'test-project',
+        isActive: true,
+        dataPath: '/repo/path',
+        createdAt: new Date().toISOString(),
+        updatedAt: new Date().toISOString(),
+      },
+      tabs: [
+        { type: 'git-diff', id: 'git-diff:commit:abc123def456', isTransient: false },
+      ],
+      activeTabId: 'git-diff:commit:abc123def456',
+      media: [],
+      dirtyPosts: new Set<string>(),
+      sidebarVisible: true,
+    });
+
+    (window as any).electronAPI = {
+      ...(window as any).electronAPI,
+      git: {
+        ...(window as any).electronAPI?.git,
+        getHistory: vi.fn().mockResolvedValue([
+          {
+            hash: 'abc123def456',
+            shortHash: 'abc123d',
+            date: '2026-02-16T10:00:00.000Z',
+            subject: 'feat: improve commit diff tabs',
+            author: 'Dev One',
+          },
+        ]),
+      },
+      app: {
+        ...(window as any).electronAPI?.app,
+        getDefaultProjectPath: vi.fn().mockResolvedValue('/repo/path'),
+      },
+      posts: {
+        ...(window as any).electronAPI?.posts,
+        get: vi.fn(),
+      },
+      chat: {
+        ...(window as any).electronAPI?.chat,
+        getConversation: vi.fn(),
+        onTitleUpdated: vi.fn(() => () => {}),
+      },
+      importDefinitions: {
+        ...(window as any).electronAPI?.importDefinitions,
+        get: vi.fn(),
+        onNameUpdated: vi.fn(() => () => {}),
+      },
+    };
+  });
+
+  it('renders commit subject in git-diff commit tab titles when available', async () => {
+    render(<TabBar />);
+
+    expect(await screen.findByText('abc123d feat: improve commit diff tabs')).toBeInTheDocument();
+    expect((window as any).electronAPI.git.getHistory).toHaveBeenCalledWith('/repo/path', 200);
+  });
+});